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David Damm Christian Fremerey Verena Thomas Michael Clausen Frank Kurth Meinard Müller 《International Journal on Digital Libraries》2012,12(2-3):53-71
In this paper, we present a digital library system for managing heterogeneous music collections. The heterogeneity refers to various document types and formats as well as to different modalities, e. g., CD-audio recordings, scanned sheet music, and lyrics. The system offers a full-fledged, widely automated document processing chain: digitization, indexing, annotation, access, and presentation. Our system is implemented as a generic and modular music repository based on a service-oriented software architecture. As a particular strength of our approach, the various documents representing aspects of a piece of music are jointly considered in all stages of the document processing chain. Our user interfaces allow for a multimodal and synchronized presentation of documents (WYSIWYH: what you see is what you hear), a score- or lyrics-based navigation in audio, as well as a cross- and multimodal retrieval. Hence, our music repository may be called a truly cross-modal library system. In our paper, we describe the system components, outline the techniques of the document processing chain, and illustrate the implemented functionalities for user interaction. We describe how the system is put into practice at the Bavarian State Library (BSB) Munich as a part of the German PROBADO Digital Library Initiative (PDLI). 相似文献
3.
1.IntroductionApproximately15milliontonsofsteeltubeandpipeproductsareconsumedintheUnitedStatesannually.Mechanicaltubesarethefeedstocksusedinthemanufactureofrollingelementbearings,hydrauliccylinders,alldagreatvarietyofpowertransmissioncomponents.Steeltubesarealsoemployedinthedrillstringsforoilandnaturalgasexplorationandrecovery.Steelpipesareusedinthetransportofgas,oilandotherfluids.ControlledThermal--MechanicalProcessing(CTMP)involvesprecisecontroloftemperature,mechanicaldeformation,andmicr… 相似文献
4.
Modeling the impact of spectral sensor configurations on the FLD retrieval accuracy of sun-induced chlorophyll fluorescence 总被引:3,自引:0,他引:3
Alexander Damm André Erler Michele Meroni Wout Verhoef 《Remote sensing of environment》2011,115(8):1882-1892
Chlorophyll fluorescence is related to photosynthesis and can serve as a remote sensing proxy for estimating photosynthetic energy conversion and carbon uptake. Recent advances in sensor technology allow remote measurements of the sun-induced chlorophyll fluorescence signal (Fs) at leaf and canopy scale. The commonly used Fraunhofer Line Depth (FLD) principle exploits spectrally narrow atmospheric oxygen absorption bands and relates Fs to the difference of the absorption feature depth of a fluorescensing and a non-fluorescensing surface. However, due to the nature of these narrow bands, Fs retrieval results depend not only on vegetation species type or environmental conditions, but also on instrument technology and processing algorithms. Thus, an evaluation of all influencing factors and their separate quantification is required to further improve Fs retrieval and to allow a reproducible interpretation of Fs signals.Here we present a modeling study that isolates and quantifies the impacts of sensor characteristics, such as spectral sampling interval (SSI), spectral resolution (SR), signal to noise ratio (SNR), and spectral shift (SS) on the accuracy of Fs measurements in the oxygen A band centered at 760 nm (O2-A). Modeled high resolution radiance spectra associated with known Fs were spectrally resampled, taking into consideration the various sensor properties. Fs was retrieved using the three most common FLD retrieval methods, namely the original FLD method (sFLD), the modified FLD (3FLD) and the improved FLD (iFLD). The analysis investigates parameter ranges, which are representative for field and airborne instruments currently used in Fs research (e.g., ASD FieldSpec, OceanOptics HR, AirFLEX, AISA, APEX, CASI, and MERIS).Our results show that the most important parameter affecting the retrieval accuracy is SNR, SR accounts for ≤ 40% of the error, the SSI for ≤ 12%, and SS for ≤ 7% of the error. A trade-off study revealed that high SR can partly compensate for low SNR. There is a strong interrelation between all parameters and the impact of specific parameters can compensate or amplify the influence of others. Hence, the combination of all parameters must be considered by the evaluation of sensors and their potential for Fs retrieval. In general, the standard FLD method strongly overestimates Fs, while 3FLD and iFLD provide a more accurate estimation of Fs. We conclude that technical sensor specifications and the retrieval methods cause a significant variability in retrieved Fs signals. Results are intended to be one relevant component of the total uncertainty budget of Fs retrieval and have to be considered in the interpretation of retrieved Fs signals. 相似文献
5.
Verification of a Radio-Based Signaling System Using the STATEMATE Verification Environment 总被引:1,自引:1,他引:0
With the trend to partially move safety-related features from courtyards into on-board control software, new challenges arise in supporting such designs by formal verification capabilities, essentially entailing the need for a model-based design process. This paper reports on the usage of the STATEMATE Verification Environment to model and verify a radio-based signaling system, a trial case study offered by the German train system company DB. It shows, that industrially sized applications can be modeled and verified with a verification tool to be offered as a commercial product by I-Logix, Inc. 相似文献
6.
Kanitz O. Windhausen Schwaibold Riffart W. Schreiber Jesser J. J. van Eck Diemair W. Ludorff J. Ph. Bruno Roßmann H. J. Steinbeck Wodsak H. Damm G. Steinhoff L. W. Jirak Fr. Bartschat H. Ketterl J. Großfeld W. Bartels G. Stamm Reichard R. Grau 《European Food Research and Technology》1937,73(5):448-504
7.
Schwaibold Schormüller Beckel W. Sutthoff Lars Erlandsen v. Skramlik W. Schreiber Kanitz Bierotte M. Steiner W. Wodsak G. Steinhoff H. J. Steinbeck Frey-Wyssling M. Gordienko K. Dirr Pawletta Stelzer W. Wodsak W. Bartels Hoepke G. Stamm Brüning W. Hämmerle Schnetka K. Felix H. Schülke Kluge Krzywanek W. Brandt Gertraude Körner-Hennig K. J. Demeter Damm J. Ph. Bruno Roßmann W. Karlowa H. Ketterl L. W. Jirak W. Preiß Diemair W. Ludorff Jahr Griebel J. J. van Eck W. Preiß C. Pyriki K. Müller Jesser K. Boresch Fr. Bartschat 《European Food Research and Technology》1939,77(3):290-336
8.
Interatom and Siemens are developing a helium-cooled Modular High Temperature Reactor. Under nominal operating conditions temperature differences of up to 120°C will occur in the 700°C hot helium flow leaving the core. In addition, cold gas leakages into the hot gas header can produce even higher temperature differences in the coolant flow. At the outlet of the reactor only a very low temperature difference of maximum ±15°C is allowed in order to avoid damages at the heat exchanging components due to alternating thermal loads. Since it is not possible to calculate the complex flow behaviour, experimental investigations of the temperature mixing in the core bottom had to be carried out in order to guarantee the necessary reduction of temperature differences in the helium. The presented air simulation tests in a 1:2.9 scaled plexiglass model of the core bottom showed an extremely high mixing rate of the hot gas header and the hot gas duct of the reactor. The temperature mixing of the simulated coolant flow as well as the leakage flows was larger than 95%. Transfered to reactor conditions this means a temperature difference of only ±3°C for the main flow at a quite reasonable pressure drop. For the cold gas leakages temperature differences in the hot gas up to 400°C proved to be permissible. The results of the simulation experiments in the Aerodynamic Test Facility of Interatom permitted to design a shorter bottom reflector of the core. 相似文献
9.
Ralf?Buscherm?hleEmail author Mark?Br?rkens Ingo?Brückner Werner?Damm Wilhelm?Hasselbring Bernhard?Josko Christoph?Schulte Thomas?Wolf 《Informatik-Spektrum》2004,27(2):146-158
Die Gewährleistung der korrekten
Funktionsweise von Hard- und Software ist ein entscheidender
Faktor bei der heutigen Systementwicklung. Dies trifft ganz
besonders auf das Gebiet der sog. sicherheitskritischen
Systeme zu, bei dem ein Systemversagen Menschenleben gefährden
kann. 相似文献
10.
The aim of this study was to determine the feasibility of minimally invasive glucose concentration measurement of a body fluid within the physiologically important range below 100 nL with a number of samples such as interstitial fluid, plasma, or whole blood using mid-infrared spectroscopy, but starting with preliminary measurements on samples of simple aqueous glucose solutions. The Fourier transform infrared spectrometer was equipped with a Golden Gate single reflection diamond attenuated total reflection (ATR) accessory and a room-temperature pyroelectric detector. As the necessary detection limits can be achieved only for dried samples within the spectrometric conditions realized by a commercial instrument, the work focused on the optimization of such ATR measurements. We achieved quantification of samples with volumes as low as 7 nL between 10 and 600 mg/dL. The standard error of prediction (SEP) for the concentration range 10-100 mg/dL is 3.2 mg/dL with full interval data between 1180 and 940 cm(-1). The performance of the prediction is given by a coefficient of variation of prediction (CV(pred) ) of 6.2%. When all samples within the whole concentration range are included, the SEP increases to 20.2 mg/dL, and hence the CV(pred) to 10.6% due to a nonlinear signal dependence on glucose concentration. A detection limit for glucose of 0.7 ng with a signal-to-noise ratio of 10 was obtained. 相似文献